School of Health and Human SciencesCopyright (c) 2017 Southern Cross University All rights reserved.http://epubs.scu.edu.au/hahs_pubs
Recent documents in School of Health and Human Sciencesen-usThu, 17 Aug 2017 01:41:45 PDT3600A pilot study to develop a tool for the assessment of students' clinical record keepinghttp://epubs.scu.edu.au/hahs_pubs/2440
http://epubs.scu.edu.au/hahs_pubs/2440Tue, 15 Aug 2017 23:49:40 PDT
Background: The ability to develop and maintain contemporaneous and accurate clinical records is a medicolegal requirement. It follows therefore that preregistration health students' skills to write such ought to be assessed. Objective: The aim of the present study is to develop an audit tool to evaluate student clinical record keeping in university on-campus clinics. Methods: The project reported on here included a literature review to identify current practice in measuring accuracy in record keeping and to identify a suitable audit tool for educational purposes. We then adapted the tool to more closely align with Australian Health Practitioner Regulatory Agency requirements. We trialled the usability of the subsequent Tool in one university health clinic – in two disciplines. In each discipline, students' clinical records from ten initial consultations and ten subsequent consultations were evaluated using the Piloted Audit Tool (PAT). Results: The PAT was difficult to use due to the grading criteria. Notwithstanding, we identified important gaps in new patient consultation notes and subsequent consultation notes in each of the two discipline groups with only a few criteria on the PAT found to be satisfactorily recorded. The most significant gaps identified in case notes taken during students' subsequent consultations with patients in each discipline. Conclusion: A tool for assessing student's case records emerged from the study. The Record Keeping Audit Tool (RKAT) will be trialled in further research, the next phase of which will be to transform the RKAT to an online tool to allow ease of administration so that larger data samples can be collected. This work will concentrate on developing a validity argument for the RKAT.
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Keri Moore et al.Diabetes educator role boundaries in Australia: a documentary analysishttp://epubs.scu.edu.au/hahs_pubs/2439
http://epubs.scu.edu.au/hahs_pubs/2439Tue, 15 Aug 2017 16:52:45 PDT
Background: Diabetes educators provide self-management education for people living with diabetes to promote optimal health and wellbeing. Their national association is the Australian Diabetes Educators Association (ADEA), established in 1981. In Australia the diabetes educator workforce is a diverse, interdisciplinary entity, with nurses, podiatrists, dietitians and several other health professional groups recognised by ADEA as providers of diabetes education. Historically nurses have filled the diabetes educator role and anecdotally, nurses are perceived to have wider scope of practice when undertaking the diabetes educator role than the other professions eligible to practise diabetes education. The nature of the interprofessional role boundaries and differing scopes of practice of diabetes educators of various primary disciplines are poorly understood. Informed by a documentary analysis, this historical review explores the interprofessional evolution of the diabetes educator workforce in Australia and describes the major drivers shaping the role boundaries of diabetes educators from 1981 until 2017.Methods: This documentary analysis was undertaken in the form of a literature review. STARLITE framework guided the searches for grey and peer reviewed literature. A timeline featuring the key events and changes in the diabetes educator workforce was developed. The timeline was analysed and emerging themes were identified as the major drivers of change within this faction of the health workforce.Results: This historical review illustrates that there have been drivers at the macro, meso and micro levels which reflect and are reflected by the interprofessional role boundaries in the diabetes educator workforce. The most influential drivers of the interprofessional evolution of the diabetes educator workforce occurred at the macro level and can be broadly categorised according to three major influences: the advent of non-medical prescribing; the expansion of the Medicare Benefits Schedule to include rebates for allied health services; and the competency movement. Conclusion: This analysis illustrates the gradual movement of the diabetes educator workforce from a nursing dominant entity, with an emphasis on interprofessional role boundaries, to an interdisciplinary body, in which role flexibility is encouraged. There is however, recent evidence of role boundary delineation at the meso and micro levels.
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Olivia King et al.Secoiridoid content of Blackstonia perfoliata in vivo and in vitrohttp://epubs.scu.edu.au/hahs_pubs/2438
http://epubs.scu.edu.au/hahs_pubs/2438Sun, 13 Aug 2017 23:06:55 PDT
This study reports the analysis of secondary metabolites of gentiopicrin, swertiamarin, and sweroside in shoot and root cultures of yellow wort (Blackstonia perfoliata), which were initiated from seeds, grown on Murashige and Skoog (MS) medium. Shoot cultures of B. perfoliata were inoculated with suspension of Agrobacterium rhizogenes strain A4M70GUS and hairy roots appeared at the infected sites after 3 wk of inoculation. Tips of adventitious roots of B. perfoliata were grown on hormone-free MS medium and three clones of the transformed roots regenerated shoots spontaneously. Gentiopicrin, swertiamarin, and sweroside were detected in both roots and shoots of B. perfoliata in vitro and in vivo, but gentiopicrin was found to be the major compound. The concentration of growth regulator in the medium affected the production of secoiridoids in B. perfoliata in vitro, where the level of gentiopicrin was higher in plants grown in the presence of indole-3-butyric acid, but the presence of 6-benzylaminopurine was inhibitory to secoiridoid production.
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Aneta Sabovljevic et al.In vitro cultures of Rhamnus fallax Boiss.(Rhamnaceae) and anthraquinones productionhttp://epubs.scu.edu.au/hahs_pubs/2437
http://epubs.scu.edu.au/hahs_pubs/2437Sun, 13 Aug 2017 18:37:29 PDTNedeljka Rosic et al.Directed evolution of mammalian cytochrome p450 enzymes involved in xenobiotic metabolismhttp://epubs.scu.edu.au/hahs_pubs/2436
http://epubs.scu.edu.au/hahs_pubs/2436Sun, 13 Aug 2017 18:29:04 PDTNedeljka Rosic et al.In vitro regeneration and transformation of Blackstonia perfoliatahttp://epubs.scu.edu.au/hahs_pubs/2435
http://epubs.scu.edu.au/hahs_pubs/2435Sun, 13 Aug 2017 17:58:59 PDTIn vitro root culture of yellow wort (Blackstonia perfoliata (L.) Huds.) was initiated on Murashige and Skoog (MS) medium. In the presence of benzylaminopurine (BAP) numerous adventitious buds formed, which developed into shoots. Presence of indole-3-butyric acid (IBA) in media significantly decreased number of buds, but increased development of lateral roots. On hormone-free medium shoots successfully rooted and developed flowers and viable seeds that formed another generation. Shoot cultures of B. perfoliata inoculated with suspension of Agrobacterium rhizogenes strain A4M70GUS developed hairy roots at 3 weeks and they were cultured on hormone-free MS medium. Spontaneous shoot regeneration occurred in 3 clones.
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A Bijelovic et al.Extending the diversity of Cytochrome P450 enzymes by DNA family shufflinghttp://epubs.scu.edu.au/hahs_pubs/2434
http://epubs.scu.edu.au/hahs_pubs/2434Tue, 08 Aug 2017 22:35:09 PDT
The cytochrome P450 enzymes involved in xenobiotic metabolism are an excellent starting point for the directed evolution of novel biocatalysts due to their wide substrate specificity. A shuffled library of three highly homologous mammalian genes (for P450 2C9, P450 2C11 and P450 2C19) was constructed by applying a modified DNA family shuffling procedure. The modifications made to the traditional DNA shuffling protocols involved non-random digestion via the use of different combinations of restriction enzymes (REs) followed by isolation of fragments under 300 bp by size-selective filtration. Shuffled cytochrome P450 mutants were co-expressed in Escherichia coli with their redox partner, NADPH-cytochrome P450 reductase (NPR). We report here how non-random fragmentation may help in chimeragenesis within the areas of low sequence similarity such as substrate recognition sites (SRSs) that are generally underrepresented in recombination using the random fragmentation process. Size-selective filtration was used to limit recovery of incompletely digested fragments and consequently minimize the chances for contamination of the shuffled library with parental forms. No parental forms could be detected in the shuffled library using restriction fragment length polymorphism (RFLP) analysis, suggesting the library was free of parental contamination. Sequencing of randomly selected mutants demonstrated a high level of chimeragenesis with on average of 8.0 ± 2.2 crossovers and a low level of mutagenesis with 5.2 ± 2.8 spontaneous mutations per ∼1.5 kbp of the full-length P450 sequence. The proportion of properly folded protein as indicated by the observation of characteristic Fe(II).CO vs. Fe(II) difference spectra was 15% (4/27) of analysed mutants. Screening of the shuffled library for indole oxidation revealed four clones with similar or higher levels of indigo pigment production to those of the parental P450s and two clones with elevated P450 expression. In this paper we present a method for the effective family shuffling of cytochrome P450 enzymes, applicable to the creation of mutant libraries with expanded metabolic diversity and with a significant proportion of functional clones.
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Nedeljka Rosic et al.Genetic transformation of Rhamnus fallax and hairy roots as a source of anthraquinoneshttp://epubs.scu.edu.au/hahs_pubs/2433
http://epubs.scu.edu.au/hahs_pubs/2433Tue, 08 Aug 2017 21:12:50 PDT
Hairy roots of Rhamnus fallax Boiss. were induced using Agrobacterium rhizogenes strain A4M70GUS. The culture established on Woody plant media (WPM) showed a typical hairy root phenotype: rapid growth, reduced apical dominance and root plagiotropism. Seven clones of R. fallax were selected on the basis of their differences in colour and the root branching. The growth of hairy root culture, measured through gain in fresh mass, was done under 16-h photoperiod or in the dark. An increase in anthraquinone (AQ) content was obtained in clones with yellow and less branched roots, like clone 1 [16.43 mg g-1(d.m.)] and clone 7 [14.21 mg g-1(d.m.)], compared with other analysed transformed and non-transformed tissue. This study presents the first report of successful transformation of any species from family Rhamnaceae by A. rhizogenes and analysis of AQ production in transformed tissue.
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Nedeljka Rosic et al.Agrobacterium rhizogenes-mediated transformation of medicinal plants from the family rhamnaceaehttp://epubs.scu.edu.au/hahs_pubs/2432
http://epubs.scu.edu.au/hahs_pubs/2432Tue, 08 Aug 2017 19:01:02 PDT
A number of plants can be successfully transformed by Agrobacterium rhizogenes through the transfer of T-DNA from agrobacteria to the plant genome. Transgenic tissue – hairy roots – is produced as a result of the transformation process. This organized, genetically stable, hormone-independent transformed tissue is capable of accomplishing complex metabolic pathways, including biosynthesis and accumulation of various secondary metabolites. Somaclonal variation is often observed among the hairy root cultures. The highlyproductive hairy root lines, containing a large amount of important metabolites can be selected and grown in vitro on hormone-free media for a long period of time, whilst preserving their biosynthetic capacities. Consequently, during the last decade, hairy root cultures have been recognized as an excellent system for in vitro generation of a large biomass of transgenic tissue that could be utilized for the extraction of desired metabolites or even in the development of new compounds through novel metabolic pathways. Species from the family Rhamnaceae are well known for their capacity to synthesize the aromatic carbohydrates, anthraquinones (AQs). These metabolites with laxative action are traditionally extracted from the bark of Frangulae cortex. Applying a genetic engineering approach, the hairy root cultures of Rhamnus fallax open a convenient alternative for the production of increased amount of medically important metabolites such as AQs while protecting natural recourses and environment
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Nedeljka RosicVersatile capacity of shuffled cytochrome P450s for dye productionhttp://epubs.scu.edu.au/hahs_pubs/2431
http://epubs.scu.edu.au/hahs_pubs/2431Tue, 08 Aug 2017 18:30:15 PDT
DNA family shuffling is a relatively new method of directed evolution used to create novel enzymes in order to improve their existing properties or to develop new features. This method of evolution in vitro has one basic requirement: a high similarity of initial parental sequences. Cytochrome P450 enzymes are relatively well conserved in their amino acid sequences. Members of the same family can have more than 40% of sequence identity at the protein level and are therefore good candidates for DNA family shuffling. These xenobiotic-metabolising enzymes have an ability to metabolise a wide range of chemicals and produce a variety of products including blue pigments such as indigo. By applying the specifically designed DNA family shuffling approach, catalytic properties of cytochrome P450 enzymes were further extended in the chimeric progeny to include a new range of blue colour formations. This mini-review evokes the possibility of exploiting directed evolution of cytochrome P450s and the novel enzymes created by DNA family shuffling for the production of new dyes.
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Nedeljka RosicA method for extracting a high-quality RNA from Symbiodinium sp.http://epubs.scu.edu.au/hahs_pubs/2430
http://epubs.scu.edu.au/hahs_pubs/2430Tue, 08 Aug 2017 18:17:22 PDT
Good quality RNA is essential for a range of analyses including microarray and gene expression studies. A number of methods for RNA extraction from symbiotic dinoflagellates were assessed for their ability to recover a high-quality RNA applicable for evaluation of gene expression profiles. The recovery and quality of the obtained RNA were evaluated with respect to UV light absorbance profiles and automated microcapillary electrophoretic RNA separation. A modified RNA extraction procedure that combines two existing commercial kits, Trizol and Qiagen RNeasy kits, was efficiently employed for the recovery of a high-quality RNA under specific homogenization conditions. Cell homogenization using glass beads at the speed of 4,500 rpm for up to 6 min resulted in a good RNA recovery and preserved RNA integrity. A high-quality RNA obtained following the described procedure was successfully applied in reverse transcriptase-polymerase chain reaction (PCR) and in quantitative PCR studies. Gene expression profiles were changed with RNA extraction procedure, with the highest transcript numbers at precise conditions of cell homogenization. RNA samples with RNA integrity number values from 6 and above were recommended for downstream applications. This sequence of RNA isolation and RNA evaluation represents a methodological improvement required for functional genomic studies in dinoflagellates.
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Nedeljka N. Rosic et al.Differential regulation by heat stress of novel cytochrome P450 genes from the dinoflagellate symbionts of reef-building coralshttp://epubs.scu.edu.au/hahs_pubs/2429
http://epubs.scu.edu.au/hahs_pubs/2429Tue, 08 Aug 2017 18:00:28 PDT
Exposure to heat stress has been recognized as one of the major factors leading to the breakdown of the coral-alga symbiosis and coral bleaching. Here, we describe the presence of three new cytochrome P450 (CYP) genes from the reef-building coral endosymbiont Symbiodinium (type C3) and changes in their expression during exposure to severe and moderate heat stress conditions. Sequence analysis of the CYP C-terminal region and two conserved domains, the “PERF” and “heme-binding” domains, confirmed the separate identities of the CYP genes analyzed. In order to explore the effects of different heat stress scenarios, samples of the scleractinian coral Acropora millepora were exposed to elevated temperatures incrementally over an 18-h period (rapid thermal stress) and over a 120-h period (gradual thermal stress). After 18 h of gradual heating and incubation at 26°C, the Symbiodinium CYP mRNA pool was approximately 30% larger, while a further 6°C increase to a temperature above the average sea temperature (29°C after 72 h) resulted in a 2- to 4-fold increase in CYP expression. Both rapid heat stress and gradual heat stress at 32°C resulted in 50% to 90% decreases in CYP gene transcript abundance. Consequently, the initial upregulation of expression of CYP genes at moderately elevated temperatures (26°C and 29°C) was followed by a decrease in expression under the greater thermal stress conditions at 32°C. These findings indicate that in the coral-alga symbiosis under heat stress conditions there is production of chemical stressors and/or transcriptional factors that regulate the expression of genes, such as the genes encoding cytochrome P450 monooxygenases, that are involved in the first line of an organism’s chemical defense.
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Nedeljka Rosic et al.Validation of housekeeping expression studies in Symbiodinium exposed to thermal and light stresshttp://epubs.scu.edu.au/hahs_pubs/2428
http://epubs.scu.edu.au/hahs_pubs/2428Tue, 08 Aug 2017 17:33:18 PDT
Unicellular photosynthetic algae (dinoflagellate) from the genus Symbiodinium live in mutualistic symbiosis with reef-building corals. Cultured Symbiodinium sp. (clade C) were exposed to a range of environmental stresses that included elevated temperatures (29°C and 32°C) under high (100 μmol quanta m−2 s −1 Photosynthetic Active Radiation) and low (10 μmol quanta m−2 s −1 ) irradiances. Using realtime RT-PCR the stability of expression for the nine selected putative housekeeping genes (HKGs) was tested. The most stable expression pattern was identified for cyclophilin and S-adenosyl methionine synthetase (SAM) followed by S4 ribosomal protein (Rp-S4), Calmodulin (Cal), and Cytochrome oxidase subunit 1 (Cox), respectively. Thermal stress alone resulted in the highest expression stability for Rp-S4 and SAM, with a minimum of two reference genes required for data normalization. For Symbiodinium exposed to both, light and thermal stresses, at least five reference genes were recommended by geNorm analysis. In parallel, the expression of Hsp90 for Symbiodinium in culture and in symbiosis within coral host (Acropora millepora) was evaluated using the most stable HKGs. Our results revealed a drop in Hsp90 expression after an 18 h-period and a 24 h-period of exposure to elevated temperatures indicating the similar Hsp90 expression profile in symbiotic and non-symbiotic environments. This study provides the first list of the HKGs and will provide a useful reference in future gene expression studies in symbiotic dinoflagellates.
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Nedeljka N. Rosic et al.Gene expression profiles of cytosolic heat shock proteins Hsp70 and Hsp90 from symbiotic dinoflagellates in response to thermal stress: possible implications for coral bleachinghttp://epubs.scu.edu.au/hahs_pubs/2427
http://epubs.scu.edu.au/hahs_pubs/2427Tue, 08 Aug 2017 17:15:16 PDT
Unicellular photosynthetic dinoflagellates of the genus Symbiodinium are the most common endosymbionts of reef-building scleractinian corals, living in a symbiotic partnership known to be highly susceptible to environmental changes such as hyperthermic stress. In this study, we identified members of two major heat shock proteins (HSPs) families, Hsp70 and Hsp90, in Symbiodinium sp. (clade C) with full-length sequences that showed the highest similarity and evolutionary relationship with other known HSPs from dinoflagellate protists. Regulation of HSPs gene expression was examined in samples of the scleractinian coral Acropora millepora subjected to elevated temperatures progressively over 18 h (fast) and 120 h (gradual thermal stress). Moderate to severe heat stress at 26°C and 29°C (+3°C and +6°C above average sea temperature) resulted in an increase in algal Hsp70 gene expression from 39% to 57%, while extreme heat stress (+9°C) reduced Hsp70 transcript abundance by 60% (after 18 h) and 70% (after 120 h). Elevated temperatures decreased an Hsp90 expression under both rapid and gradual heat stress scenarios. Comparable Hsp70 and Hsp90 gene expression patterns were observed in Symbiodinium cultures and in hospite, indicating their independent regulation from the host. Differential gene expression profiles observed for Hsp70 and Hsp90 suggests diverse roles of these molecular chaperones during heat stress response. Reduced expression of the Hsp90 gene under heat stress can indicate a reduced role in inhibiting the heat shock transcription factor which may lead to activation of heat-inducible genes and heat acclimation.
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Nedeljka Rosic et al.Mycosporine-like amino acids from coral dinoflagellateshttp://epubs.scu.edu.au/hahs_pubs/2426
http://epubs.scu.edu.au/hahs_pubs/2426Tue, 08 Aug 2017 16:45:12 PDT
Coral reefs are one of the most important marine ecosystems, providing habitat for approximately a quarter of all marine organisms. Within the foundation of this ecosystem, reef-building corals form mutualistic symbioses with unicellular photosynthetic dinoflagellates of the genus Symbiodinium. Exposure to UV radiation (UVR) (280 to 400 nm) especially when combined with thermal stress has been recognized as an important abiotic factor leading to the loss of algal symbionts from coral tissue and/or a reduction in their pigment concentration and coral bleaching. UVR may damage biological macromolecules, increase the level of mutagenesis in cells, and destabilize the symbiosis between the coral host and their dinoflagellate symbionts. In nature, corals and other marine organisms are protected from harmful UVR through several important photoprotective mechanisms that include the synthesis of UV-absorbing compounds such as mycosporine-like amino acids (MAAs). MAAs are small (<400-Da), colorless, water-soluble compounds made of a cyclohexenone or cyclohexenimine chromophore that is bound to an amino acid residue or its imino alcohol. These secondary metabolites are natural biological sunscreens characterized by a maximum absorbance in the UVA and UVB ranges of 310 to 362 nm. In addition to their photoprotective role, MAAs act as antioxidants scavenging reactive oxygen species (ROS) and suppressing singlet oxygen-induced damage. It has been proposed that MAAs are synthesized during the first part of the shikimate pathway, and recently, it has been suggested that they are synthesized in the pentose phosphate pathway. The shikimate pathway is not found in animals, but in plants and microbes, it connects the metabolism of carbohydrates to the biosynthesis of aromatic compounds. However, both the complete enzymatic pathway of MAA synthesis and the extent of their regulation by environmental conditions are not known. This minireview discusses the current knowledge of MAA synthesis, illustrates the diversity of MAA functions, and opens new perspectives for future applications of MAAs in biotechnology.
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Nedeljka Rosic et al.New-old hemoglobin-like proteins of symbiotic dinoflagellateshttp://epubs.scu.edu.au/hahs_pubs/2425
http://epubs.scu.edu.au/hahs_pubs/2425Tue, 08 Aug 2017 16:26:29 PDT
Symbiotic dinoflagellates are unicellular photosynthetic algae that live in mutualistic symbioses with many marine organisms. Within the transcriptome of coral endosymbionts Symbiodinium sp. (type C3), we discovered the sequences of two novel and highly polymorphic hemoglobin-like genes and proposed their 3D protein structures. At the protein level, four isoforms shared between 87 and 97% sequence identity for Hb-1 and 78–99% for Hb-2, whereas between Hb-1 and Hb-2 proteins, only 15–21% sequence homology has been preserved. Phylogenetic analyses of the dinoflagellate encoding Hb sequences have revealed a separate evolutionary origin of the discovered globin genes and indicated the possibility of horizontal gene transfer. Transcriptional regulation of the Hb-like genes was studied in the reef-building coral Acropora aspera exposed to elevated temperatures (6–7°C above average sea temperature) over a 24-h period and a 72-h period, as well as to nutrient stress. Exposure to elevated temperatures resulted in an increased Hb-1 gene expression of 31% after 72 h only, whereas transcript abundance of the Hb-2 gene was enhanced by up to 59% by both 1-day and 3-day thermal stress conditions. Nutrient stress also increased gene expression of Hb-2 gene by 70%. Our findings describe the differential expression patterns of two novel Hb genes from symbiotic dinoflagellates and their polymorphic nature. Furthermore, the inducible nature of Hb-2 gene by both thermal and nutrient stressors indicates a prospective role of this form of hemoglobin in the initial coral–algal responses to changes in environmental conditions. This novel hemoglobin has potential use as a stress biomarker.
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Nedeljka Rosic et al.Phylogenetic analysis of genes involved in mycosporine-like
amino acid biosynthesis in symbiotic dinoflagellateshttp://epubs.scu.edu.au/hahs_pubs/2424
http://epubs.scu.edu.au/hahs_pubs/2424Tue, 08 Aug 2017 16:16:22 PDT
Mycosporine-like amino acids (MAAs) are multifunctional secondary metabolites involved in photoprotection in many marine organisms. As well as having broad ultraviolet (UV) absorption spectra (310–362 nm), these biological sunscreens are also involved in the prevention of oxidative stress. More than 20 different MAAs have been discovered so far, characterized by distinctive chemical structures and a broad ecological distribution. Additionally, UV-screening MAA metabolites have been investigated and used in biotechnology and cosmetics. The biosynthesis of MAAs has been suggested to occur via either the shikimate or pentose phosphate pathways. Despite their wide distribution in marine and freshwater species and also the commercial application in cosmetic products, there are still a number of uncertainties regarding the genetic, biochemical, and evolutionary origin of MAAs. Here, using a transcriptome-mining approach, we identify the gene counterparts from the shikimate or pentose phosphate pathway involved in MAA biosynthesis within the sequences of the reef-building coral symbiotic dinoflagellates (genus Symbiodinium). We also report the highly similar sequences of genes from the proposed MAA biosynthetic pathway involved in the metabolism of 4-deoxygadusol (direct MAA precursor) in various Symbiodinium strains confirming their algal origin and conserved nature. Finally, we reveal the separate identity of two O-methyltransferase genes, possibly involved in MAA biosynthesis, as well as nonribosomal peptide synthetase and adenosine triphosphate grasp homologs in symbiotic dinoflagellates. This study provides a biochemical and phylogenetic overview of the genes from the proposed MAA biosynthetic pathway with a focus on coral endosymbionts.
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Nedeljka RosicDNA shuffling of cytochromes P450 for indigoid pigment productionhttp://epubs.scu.edu.au/hahs_pubs/2423
http://epubs.scu.edu.au/hahs_pubs/2423Mon, 07 Aug 2017 22:23:26 PDT
DNA family shuffling is a powerful method of directed evolution applied for the generation of novel enzymes with the aim of improving their existing features or creating completely new enzyme properties. This method of evolution in vitro requires parental sequences containing a high level of sequence similarity, such as is found in family members of cytochrome P450 enzymes. Cytochromes P450 (P450s or CYPs) are capable of catalyzing a variety of chemical reactions and generating a wide range of products including dye production (e.g., pigments indigo and indirubin). Application of the method of DNA family shuffling described here has enabled us to create novel P450 enzymes and to further extend the capacity of P450 to oxidize indole, leading to pigment formation.
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Nedeljka RosicEarly transcriptional changes in the reef-building coral Acropora aspera in response to thermal and nutrient stresshttp://epubs.scu.edu.au/hahs_pubs/2422
http://epubs.scu.edu.au/hahs_pubs/2422Mon, 07 Aug 2017 21:53:08 PDT

Background

Changes to the environment as a result of human activities can result in a range of impacts on reef building corals that include coral bleaching (reduced concentrations of algal symbionts), decreased coral growth and calcification, and increased incidence of diseases and mortality. Understanding how elevated temperatures and nutrient concentration affect early transcriptional changes in corals and their algal endosymbionts is critically important for evaluating the responses of coral reefs to global changes happening in the environment. Here, we investigated the expression of genes in colonies of the reef-building coral Acropora aspera exposed to short-term sub-lethal levels of thermal (+6°C) and nutrient stress (ammonium-enrichment: 20 μM).

Results

The RNA-Seq data provided hundreds of differentially expressed genes (DEGs) corresponding to various stress regimes, with 115 up- and 78 down-regulated genes common to all stress regimes. A list of DEGs included up-regulated coral genes like cytochrome c oxidase and NADH-ubiquinone oxidoreductase and up-regulated photosynthetic genes of algal origin, whereas coral GFP-like fluorescent chromoprotein and sodium/potassium-transporting ATPase showed reduced transcript levels. Taxonomic analyses of the coral holobiont disclosed the dominant presence of transcripts from coral (~70%) and Symbiodinium (~10-12%), as well as ~15-20% of unknown sequences which lacked sequence identity to known genes. Gene ontology analyses revealed enriched pathways, which led to changes in the dynamics of protein networks affecting growth, cellular processes, and energy requirement.

Conclusions

In corals with preserved symbiont physiological performance (based on Fv/Fm, photo-pigment and symbiont density), transcriptomic changes and DEGs provided important insight into early stages of the stress response in the coral holobiont. Although there were no signs of coral bleaching after exposure to short-term thermal and nutrient stress conditions, we managed to detect oxidative stress and apoptotic changes on a molecular level and provide a list of prospective stress biomarkers for both partners in symbiosis. Consequently, our findings are important for understanding and anticipating impacts of anthropogenic global climate change on coral reefs.

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Nedeljka Rosic et al.Extraction and analysis of Mycosporine-Like Amino Acids in marine algaehttp://epubs.scu.edu.au/hahs_pubs/2421
http://epubs.scu.edu.au/hahs_pubs/2421Mon, 07 Aug 2017 21:23:07 PDT
Marine organisms use mycosporine-like amino acids (MAAs) as biological sunscreens for the protection from damaging ultraviolet (UV) radiation and the prevention of oxidative stress. MAAs have been discovered in many different marine and freshwater species including cyanobacteria, fungi, and algae, but also in animals like cnidarian and fishes. Here, we describe a general method for the isolation and characterization of MAA compounds from red algae and symbiotic dinoflagellates isolated from coral hosts. This method is also suitable for the extraction and analyses of MAAs from a range of other algal and marine biota.
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Nedeljka N. Rosic et al.